Lateral inhibition between banks of orientation selective channels predicts shape context effects: A tilt-illusion field

Direction-Specific Tilt Illusion: With and without Gaze Fixation

Perception ◽

10.1068/p110529 ◽

1982 ◽

Vol 11 (5) ◽

pp. 529-533 ◽

Cited By ~ 3

Author(s):

Thom Carney

Keyword(s):

Lateral Inhibition ◽

Tilt Aftereffect ◽

Tilt Illusion ◽

Gaze Fixation ◽

Test Grating

The perceived orientation of a test grating is rotated from its veridical orientation if an annulus grating with a similar orientation is present. The magnitude of this misperception was measured and found to be greater when the two gratings moved in the same direction than when they moved in opposite directions. This demonstration of a direction-specific tilt illusion is similar to the previously demonstrated direction-specific tilt aftereffect—which is to be expected if similar mechanisms are responsible for both phenomena. If the tilt illusion is caused by lateral inhibition between orientation-selective units, then these findings indicate that such inhibition is principally between units with similar orientation and direction of motion selectivities.

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Stochastic re-calibration: contextual effects on perceived tilt

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2006.3634 ◽

2006 ◽

Vol 273 (1601) ◽

pp. 2681-2686 ◽

Cited By ~ 29

Author(s):

Joshua A Solomon ◽

Michael J Morgan

Keyword(s):

Visual Field ◽

Visual System ◽

Lateral Inhibition ◽

Human Visual System ◽

Contextual Effects ◽

Letter Recognition ◽

Tilt Illusion ◽

Reference Orientation ◽

The Difference

The human visual system exaggerates the difference between the tilts of adjacent lines or grating patches. In addition to this tilt illusion, we found that oblique flanks reduced acuity for small changes of tilt in the centre of the visual field. However, no flanks—regardless of their tilts—decreased sensitivity to contrast. Thus, the foveal tilt illusion should not be attributed to orientation-selective lateral inhibition. Nor is it similar to conventional crowding, which typically does not impair letter recognition in the fovea. Our observers behaved as though the reference orientation (horizontal) had a small tilt in the direction of the flanks. We suggest that the extent of this re-calibration varies randomly over trials, and we demonstrate that this stochastic re-calibration can explain flank-induced acuity loss in the fovea.

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Orientation-Selective Inhibition and Binocular Rivalry

Perception ◽

10.1068/p070207 ◽

1978 ◽

Vol 7 (2) ◽

pp. 207-214 ◽

Cited By ~ 9

Author(s):

Peter Walker

Keyword(s):

Negative Correlation ◽

Binocular Rivalry ◽

Lateral Inhibition ◽

Sensory Input ◽

Visual Stimuli ◽

Interocular Transfer ◽

Selective Inhibition ◽

Tilt Illusion ◽

Fundamental Parameters ◽

Dichoptic Viewing

It is hypothesized that a negative correlation exists between the readiness with which two visual stimuli display rivalry and the magnitude of the inhibition effects between the corresponding neural channels. With binocular rivalry being more readily observed than monocular rivalry, it is predicted that lateral inhibition between neural channels selectively sensitive to such fundamental parameters as orientation, is primarily confined to those monocularly driven channels deriving their sensory input from the same eye. In confirmation, it is shown that the visual tilt illusion, thought to reflect lateral inhibition between orientation-sensitive channels, is very much reduced under dichoptic viewing conditions. Moreover, it is shown that those subjects displaying the greatest interocular transfer of the illusion least readily experience binocular rivalry.

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